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Old March 8th 08, 01:56 PM posted to rec.radio.amateur.antenna
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"Art Unwin" wrote in message
...
On Mar 7, 11:19 pm, (Richard Harrison)
wrote:
Art wrote:

"No where can I find reference to "size" in what the masters state."

It`s there if you look. Kraus is a certified master. In the newest
edition, the 3rd, of "Antennas" is found on page 12:
"The basic equation of radiation may be expressed simply as
IL=QV, where
I=time changing current
L=length of current element
Q=charge,C
V=time change of velocity or acceleration
Thus, time changing current radiates and accelerated charge radiates.
For steady-state harmonic radiation, we usually focus on current. For
transients or pulses, we focus on charge."

The above is the beginning of the chapter on "Antenna Basics". Everyone
interested in antennas needs ready access to this important book.

Best regards, Richard Harrison, KB5WZI


But you arer forgettfull Richard, my antenna is a full wavelength
which meets
Maxwells requirements, it is just that the volume is small despite the
wavelength.
It is also not in conflict with "antenna basics" alluded to above. I
don't
understandwhat the beef is. Why are so many hams alarmed at the idea?
Regards
Art


its called 'experience' by most and 'knowledge' by those in the know.


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Old March 8th 08, 04:21 PM posted to rec.radio.amateur.antenna
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Art wrote:
"---my antenna is a full wavelength which meets Maxwell`s requirements,
it is just that the volume is small despite the wavelength."

In 1949, I worked at the KPRC-KXYZ broadcast plant. Another operator
there, J.L. Davis, W5LIT had a new 1949 Ford in which he installed a
surplus ART-13 and a PE-103 dynamotor. For an antenna he wound wire turn
by turn on a bamboo pole until it was resonant on a slice of the
75-meter band.

When J.L. modulated, Q in the coil produced a tip corona on the first
good peak and modulation became loud without a receiver.

The 20th edition of the ARRL Antenna Book on page 16-13 says this about
continuously loaded antennas: "The general approach has been to use a
coil made from heavy wire (#14 or larger), with length-to-diameter
ratios as high as 21. British experimeters have reported good results
with 8-foot overall length on the 1.8- and 3.5 MHz bands. The idea of
making the entire antenna out of one section of coil has been tried with
some success."

Art`s antenna containing a "full wavelength" of wire would likely
feature a greater loss than J.L.`s 1/4-wave resonant coil from simply a
greater length of wire while both have peactances balanced to zero.
Art`s lower Q would probably kill the corona, increase the bandwidth,
while losing the gain that a fullwave straight conductor enjoys.

Cecil can probably report on results of continuously loaded mobile
antennas versus a bug catcher loaded whip in the California shoot-outs.

Best regards, Richard Harrison, KB5WZI


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Old March 8th 08, 06:37 PM posted to rec.radio.amateur.antenna
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On Mar 8, 10:21 am, (Richard Harrison)
wrote:
Art wrote:

"---my antenna is a full wavelength which meets Maxwell`s requirements,
it is just that the volume is small despite the wavelength."

In 1949, I worked at the KPRC-KXYZ broadcast plant. Another operator
there, J.L. Davis, W5LIT had a new 1949 Ford in which he installed a
surplus ART-13 and a PE-103 dynamotor. For an antenna he wound wire turn
by turn on a bamboo pole until it was resonant on a slice of the
75-meter band.

When J.L. modulated, Q in the coil produced a tip corona on the first
good peak and modulation became loud without a receiver.

The 20th edition of the ARRL Antenna Book on page 16-13 says this about
continuously loaded antennas: "The general approach has been to use a
coil made from heavy wire (#14 or larger), with length-to-diameter
ratios as high as 21. British experimeters have reported good results
with 8-foot overall length on the 1.8- and 3.5 MHz bands. The idea of
making the entire antenna out of one section of coil has been tried with
some success."

Art`s antenna containing a "full wavelength" of wire would likely
feature a greater loss than J.L.`s 1/4-wave resonant coil from simply a
greater length of wire while both have peactances balanced to zero.
Art`s lower Q would probably kill the corona, increase the bandwidth,
while losing the gain that a fullwave straight conductor enjoys.

Cecil can probably report on results of continuously loaded mobile
antennas versus a bug catcher loaded whip in the California shoot-outs.

Best regards, Richard Harrison, KB5WZI


There are no loads on my antenna so your statements are irrelavent
Art
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Old March 15th 08, 01:46 PM posted to rec.radio.amateur.antenna
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Default Antenna physical size

On Mar 8, 11:21 am, (Richard Harrison)
wrote:
Art wrote:

"---my antenna is a full wavelength which meets Maxwell`s requirements,
it is just that the volume is small despite the wavelength."

In 1949, I worked at the KPRC-KXYZ broadcast plant. Another operator
there, J.L. Davis, W5LIT had a new 1949 Ford in which he installed a
surplus ART-13 and a PE-103 dynamotor. For an antenna he wound wire turn
by turn on a bamboo pole until it was resonant on a slice of the
75-meter band.

When J.L. modulated, Q in the coil produced a tip corona on the first
good peak and modulation became loud without a receiver.

The 20th edition of the ARRL Antenna Book on page 16-13 says this about
continuously loaded antennas: "The general approach has been to use a
coil made from heavy wire (#14 or larger), with length-to-diameter
ratios as high as 21. British experimeters have reported good results
with 8-foot overall length on the 1.8- and 3.5 MHz bands. The idea of
making the entire antenna out of one section of coil has been tried with
some success."

Art`s antenna containing a "full wavelength" of wire would likely
feature a greater loss than J.L.`s 1/4-wave resonant coil from simply a
greater length of wire while both have peactances balanced to zero.
Art`s lower Q would probably kill the corona, increase the bandwidth,
while losing the gain that a fullwave straight conductor enjoys.

Cecil can probably report on results of continuously loaded mobile
antennas versus a bug catcher loaded whip in the California shoot-outs.

Best regards, Richard Harrison, KB5WZI


Considering that it meets Maxwells requirements and is at least a
wavelenght
of a radiator my expectations are much higher than yours
I suspect that the output will exceed that of a 160 M antenna which
has a ground plane.
I also suspect that if I diddn't concentrated so much on small
physical size it could easily be uprated
to compete with a yagi!
I would anticipate that in a couple of years the top band will have
twice as many users that it has now.
I am hoping also that its small size will allow for receiving
abililities in line with the angle of incoming
radiation via its manouvarability. Of course if all is already known
about radio this would seem impossible
but in a few weeks I myself will have a few QSOs to see how it matches
up to my expectations.
The archives show all the building instruction but it appears that
readers have concentrated on
nonsensical retorts without reading the content. If an antenna is at
least off one wavelength
and is in equilibrium I see no reason why it should not beat existing
antennas with ground plane losses
regardless of its shape or size. Time will tell. Either way the
experimental trail undertaken I have found to
be very rewarding as many other amateurs have had when experimenting
with antennas and who refuse
to accept that all is known
Art
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Old March 9th 08, 12:16 PM posted to rec.radio.amateur.antenna
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Art,
"Why are so many hams alarmed at the idea?"
Because of the way you describe things, words used for a distinction
between things that just don't make sense. At least that's why I
'wonder' at times. After seeing your 'methods' of doing/saying
things, you just don't 'alarm' me much. You DO make me 'wonder'
though...
- 'Doc


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Old March 9th 08, 02:23 PM posted to rec.radio.amateur.antenna
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On Mar 9, 7:16 am, wrote:
Art,
"Why are so many hams alarmed at the idea?"
Because of the way you describe things, words used for a distinction
between things that just don't make sense. At least that's why I
'wonder' at times. After seeing your 'methods' of doing/saying
things, you just don't 'alarm' me much. You DO make me 'wonder'
though...
- 'Doc


You may be right We will just have to wait and see how things turn
out.
If it works then I am smart and if it is useless then I fit what
everybody
thinks of me. No damage done either way.
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Old March 10th 08, 01:38 PM posted to rec.radio.amateur.antenna
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Default Antenna physical size

On Mar 9, 9:23 am, Art Unwin wrote:
On Mar 9, 7:16 am, wrote:

Art,
"Why are so many hams alarmed at the idea?"
Because of the way you describe things, words used for a distinction
between things that just don't make sense. At least that's why I
'wonder' at times. After seeing your 'methods' of doing/saying
things, you just don't 'alarm' me much. You DO make me 'wonder'
though...
- 'Doc


You may be right We will just have to wait and see how things turn
out.
If it works then I am smart and if it is useless then I fit what
everybody
thinks of me. No damage done either way.


My replacement antenna for the one I sent away is comming along just
fine
and I will probably be active on the air in a few weeks.
The new one is about two shoe box size and will be connected to a tilt/
scan
mechanism so that I can fully determine all the characteristics in
real life circumstances.
The frequency spread is down to the top of the broadcast band and it
will be controlled by my
Icom where I will disconect the inbuilt tuner motors and reconnect to
my antenna.
This should then ensure that the antenna is always in equilibrium
screw driver style
when I am on the air regardless of the band in use.Hoping to change
polarity in QSO's
to investigate the differences. Hopefully this summer the pan tilt
will also be made
automatic for best polarity reception which will then allow for the
addition of a dish reflector.
Bought myself a new thin Mac laptop which is exciting to use. There is
a free NEC 2
program available(cocoanec) so it is getting difficult to determine
what to work on.
Spring is coming and life is good despite the naysayers.
Have a happy day
Regards
Art
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